What is the safest (and reliable) way to deal with unused input/output pins of serial comm. chips like MAX232, ST3232, etc..
So far i'm familiar with these three options:
- Input and Output Not connected
- Tie inputs toghether (ie. MAX232 connect pint 10 to 11, and 8 to 13), output not connected
- Pull-up/Pull-down resistors to input, output not connected.
I've seen this setups many times and never with a proper explanation as of why it was chosen. Maybe there's another setup i'm not familiar as well.